Our objective is to develop novel image-guided, less-invasive techniques for hip revision surgery. From September 2005 to December 2006 approximately 51300 revision Total Hip Arthroplasties (THAs) were performed in the United States with an average cost of $54500 per each revision surgery. The number of both primary and revision hip arthroplasty is projected to almost double between 2005 and 2030. Some of the goals of THA revision surgery are to eliminate the particle debris, remove all osteolytic lesions from the bone and other tissues, and replace the articulating polyethylene liner. The less-invasive approach attempts to preserve acetabular and femoral components of the THA, as long as they are firmly fixed to the bone, and only replaces the acetabular polyethylene liner. In the less-invasive approach, lesions are accessed through existing screw holes of the well-fixed metal acetabular component. Here, a major challenge for the surgeon is determining that the lesion is fully debrided and that the lesion is fully bone grafted. One study suggests that, on average, less than 50% of the lesion is actually grafted due to difficulty in accessing the areas o osteolysis behind the acetabular component. Standard surgical instruments are unable to access the cavities deep behind the component (sometimes extending all the way to the sacro-iliac joint). Because direct visual inspection and access to the areas requiring debridment is not always possible, many times surgeons have to completely remove THA components because they cannot otherwise clean the osteolytic lesions. Component removal increases risk of fracture and pelvic dissociation, and makes for remarkably long (i.e. 4-6 months after surgery) recovery and bed-rest periods in elderly patients. With less-invasive approaches patients may start normal weight bearing immediately after the surgery. This procedure, therefore, would highly benefit from the use of less-invasive approaches and highly dexterous (robotically-assisted) instruments to access these very difficult to reach areas within the body. To our knowledge, robotically-assisted, less-invasive revision techniques for treatment of osteolytic bone are not developed. In particular, the design of the appropriate tools and dexterous manipulators for the treatment and removal of the osteolytic lesions poses unique challenges because of the requirements for both structural strength and flexibility. We propose to develop a prototype surgical workstation for preoperative planning, and real-time intraoperative monitoring, navigation, and updating of plans during the revision surgery.